Bobbin-handling mechanism



Aug. 5, 1 969 5 Sheets-Sheet 1 Filed Aug. 25, 1967 Milka D. D'imifrov INVENTOR Fig.1

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5, 1959 MILKO 0. DIMITROV 3,458,984

BOBBIN'HANDLING MECHANISM 3 Sheets-Sheet 2 Filed Aug. 25, 1967 Milka D. Dimifrov INVENTOR.

fl- 5, 1969 MILKO D. DIMITROV 3,458,984

BOBBIN'HANDLING MECHANISM Filed Aug. 25, 1967 s Sheets-Sheet a Milka D. Dimirrav INVENTOR.

a At torney United States Patent 3,458,984 BOBBlN-HANDLING MECHANISM Milko Dimitrov Dimitrov, Sofia, Bulgaria, assignor to DSO Tejko I Obshto Mashinostroene, Sofia, Bulgaria,

a State Economic Association of Bulgaria Filed Aug. 25, 1967, Ser. No. 663,258 Claims priority, applicationslgulgaria, Aug. 29, 1966,

,0 Int. Cl. D01h 9/10 US. Cl. 5753 14 Claims ABSTRACT OF THE DISCLOSURE In a machine for the building of bobbins on spool cores carried by a bank of horizontally moving upright spindles, full bobbins are removed and new cores are placed on the spindles by a mechanism which comprises a series of units each including a donning fork and a dotting fork which are .tiltable about horizontal axes, the mechanism including a triangular frame along whose ascending side the dotfing forks move in recumbent position and pick up respective bobbins, each dofiing fork being erected on reaching the apex of the triangle, while on the descending side the previously erected donning forks loaded with fresh cores are placed in recumbent position to deposite each core on an empty spindle.

My present invention relates to an automatic doffer for ring spinning frames and, more particu-arly, to a device for removing full bobbins from ring spinning or twisting frames or machines and replacing them by empty bobbins.

The device of the present invention is designed to move parallel to the row of spindles and to be associated with the spinning or twisting machine.

It has already been proposed to provide devices for automatic replacing full bobbins by empty spools in conjunction with spinning and twisting such devices operating continuously or periodically. In most cases, the machine is controlled by cam mechanism. Continuously operating doffing units are characterized by the fact that it is ditficult to provide the requisite cam-profile curve for smooth operation. For example, in addition to providing uniform and smooth movement of the mechanism, the cams in practice must have a low pressure angle and therefore may be of increased length, while requiring corresponding increase of the cam-follower and other mechanism operated thereby. Moreover, the conventional practice of removing the full bobbins by corresponding them at their upper end requires the use of special bobbin cores with hardened extremities. Moreover, the engagement of the bobbins at their lower ends is hindered by the traveller or balloon-control rings.

It is an object of the present invention to provide an improved device for the automatic dofling of twisting and spinning frames of the character described.

This object, and others which will be apparent hereinafter, is attained by providing, in a machine for the building of bobbins or respective spool cores, carried by a bank of horizontally moving upright spindles, a mechanism comprising a series of units each including a donning fork and a doffing fork which are tiltable about horizontal axis for placing empty cores on the respective spindles and removing full bobbins therefrom. The mechice anism includes a triangular frame having ascending and descending sides inclined to the horizontal and along the ascending side of which the dofling fork moves in recumbent position and pick up respective bobbins. Each dofiing fork is erected on reaching the apex of the triangle, while in the descending side the previously erected donning forks, loaded with fresh or empty cores, are placed in recumbent position to deposit each core on an empty spindle. The device makes use of an endless chain positioned via suitable guide means and sprockets in the form of an isosceles triangle on which are fixed the units having forks for removing full bobbins and depositing empty ones. The device also includes a system for feeding the empty cores to the donning forks and cutting the thread of a full wound bobbin to allow it to be removed by the doffing fork.

The invention is described in greater detail hereinafter with reference to the accompanying drawing in which:

FIG. 1 is a side view of the doffer alongside a travelling row of spindles of a spinning or twisting machine;

FIG. 2 is an elevational view of a unit carried by the chain along the triangular path and provided with forks for removing the full bobbins (dotling forks) and forks for placing empty cores upon the spindle;

FIG. 3 is a plan view of the thread-cutting mechanism according to the present invention; and

FIG. 4 is a detail of a lock for the forks of one of these units.

In FIG. 1, I show a system according to the present invention in which a triangle guide frame T is positioned on a base adjacent to spinning and twisting machine which sustains continuous flow of spindles therepast. On this chain, which passes over idlers at the apexes of the triangle, there are mounted a number of units 2 (FIG. 2) which may be referred to hereinafter as dofling and donning units.

Each unit (FIG. 2) comprises a base 1 on which a sector 2 is pivotally mounted for purposes to be discussed in greater detail hereinafter.

The unit also comprises a dofiing fork 3 and a donning fork 4, both shown in their erected positions. A lock 5 retains the donning fork 3 in its elevated position while locks 7 and 8 are provided to hold the sector 2 in its extreme angular positions. A lifting lever 9 is carried by the sector 2 and serves to elevate the dotfing fork 3 while locking 10 retains the donning fork in position for dropping a bobbin or a spindle.

Referring again to FIG. 1, it can be seen that the ascending path of the isosceles triangle traversed by each dofiing and donning unit runs alongside the mouth of a magazine 11 for delivering empty cores S to the donning fork 4 of the units as they ride up along the ascending side of the device. The cores pass along a ramp 25 from the magazine 11 under the control of a plate 13 actuated by a crank connected by a belt to the chain drive for the unit (lefthand side in FIG. 1) into a chute 12 from which they are dispensed to the donning forks. A yarn cutting device, seen only fragmentarily in the center of the isoceles triangle in FIG. 1, serves to sever the yarn of the full bobbin as they are removed and carried away. This yarn-cutting device, shown in greater detail in FIG. 3, comprises a yarndeflectingwire or deviator 14 adapted to intercept the yarn of each spool as the spindles pass successively beneath it. The deviator 14 co-operates with a knife or blade 15 and a pressing bar 16 which bears against the spools as is discussed in greater detail hereinafter.

The isosceles triangle defines the path of the units which lie in a plane parallel to the plane of the spindle axes, the path having ascending and descending sides along the inclined flanks of the triangle and a horizontal stretch running counter to the direction along which the spindles advance at the base of the triangle.

At the lower path of the ascending side of the triangular path (i.e. the left in FIG. 1), I provide an electromagnet 17 which has a tongue that extends into the path of the units to trip the latch holding the doffing fork 3 in its erected or vertical position. A spring constituting part of the latch swings the dofling fork 3 downwardly, i.e. into a recumbent or generally horizontal position as will be apparent with respect to the unit at the lower left-hand side of the triangular path in FIG. 1, whereby the fork 3 engages a full bobbin at the point at which the triangular path of the units cross the horizontal row of upright bobbins. The fork 3 (FIG. 2) is formed with a bifurcation with catcher members 18 adapted to engage the full bobbin and a leaf-type spring 19 by means of which the catchers are biased inwardly and are frictionally held against the full bobbin so as to hug the latter. The continued movement of the unit upwardly along the triangular path as the spindles continue their movement to the right (FIG. 1) results in withdrawal of the full bobbin from its spindle to release the bobbin and empty the spindles Sp. The lever 9 of the ascending unit (see FIGS. 1 and 2) is then engaged by a guide bar 20 which functions to lift the fork 3 into its erected position in which it holds the bobbin B such that its axis is horizontal (see the unit at the upper portion of the ascending stretch of the triangular path in FIG. 1). Latch 5 relocks to retain the doffing fork 3 in this position.

The lock and locks 7 and 8 are operated by a ratchet. Means may be provided to enable a circuit breaker to stop the motors of the apparatus when a damaged spool or a wrongly inserted spool is engaged by the forks 4.

In the upper position, the lock 8 (FIG. 2) of the unit rising along the triangle is unlatched by a ratchet arrangement enabling the sector 2 with the fork 4 carrying the empty core S picking up from the chute 12 to swing until latch 7 engages to lock the sector 2 in a position of the fork such that the empty spool S is oriented parallel to the spindle axis but generally horizontal as shown in FIGS. 1 and 2. A further electromagnet 22 on the descending side of the path triggers the lock 6 of the donning fork 4, thereby allowing the fork to swing downwardly toward the plane of the spindle deposit its empty bobbin onto the spindle from the upper end. Lock 10 (FIG. 4) holds the donning fork in its recumbent position until a guide 24 elevates the fork 4 into its upright position in which it is latched by lock 6. The empty spool is received in springloaded catches 23 from which the core is drawn as the spindle carrying it passes beyond the reach of the fork. As the units are carried along the lower pass of the triangle, a detent arrangement unlock the latch 7 and the sector 2 is enabled to return to its initial position by the action of a spring, whereupon latch 8 re-engages.

An ejector ramp 27 lifts the full bobbin B from the upright fork 3 of each unit as it moves downwardly along the triangle. The bobbin passes over the ejector into a magazine. During the removal of the full bobbin from the spindle, the thread deflector 14 catches the yarn and guides it toward the knife blade which severs the thread to release the full bobbin. The pressing band 16 frictionally retains the cut thread and until a new core is inserted while a thread deflector 28 (FIG. 1) is designed to return threads which terminate in front. The contacts 29 are actuated by the train of spindles to energize electromagnet 17 when the first spindle arrives and de-energize the electromagnet when the last spindle clears. Contacts 30 come also operated by a plate along the spindle train, energizes electromagnet 22 upon arrival of the first spindle and switches it out on passage of the last spindle therepast. A sprocket 31 drives the main chain while the dofl'er is driven by a motor 32.

I claim:

1. A device for the automatic dofiing of bobbins from and replacement of empty spools on a spinning and twisting machine, comprising, in combination with a spinning or twisting machine having a succession of spindles moving along a transport path and lying in a plane while spools carried by said bobbins are wound with yarn, a donning and doffing station alongside said path and including:

an endless chain lying in a plane parallel to the plane of said spindles and adjacent said transport path while defining an isosceles triangle having a base parallel to said path and ascending and descending inclined sides extending from said base in the plane of said chain to an apex above the spindles displaceable therepast;

a plurality of dofiing and donning units entrained by said chain, each of said units including a dofiing fork engageable with full bobbins carried by spindles upon movement past the ascending sides of said chain for lifting said full bobbins from their spindles as said units travel upwardly along side ascending side, and a donning fork adapted to receive an empty spool for emplacing same on the spindles as they pass the descending side of the triangle while the units move downwardly therealong;

a magazine positioned along said ascending side for delivering empty spools to said donning forks; and

means along said descending side for removing full bobbins from said dofling fork.

2. The device defined in claim 1 wherein said forks are pivotal on the respective units from a recumbent position in which said forks extend transversely to said planes for engagement of the full bobbin by said dofling fork and emplacement of the empty spools on said spindles by said donning fork into elevated positions for discharge of said full bobbins by said dofiing fork and receipt of empty spools by said donning fork, said units each being further provided with locking means for temporarily releasably retaining each fork selectively in its recumbent and elevated positions.

3. The device defined in claim 2, further comprising a guide bar along the ascending side of said triangle for elevating said dofiing fork from its recumbent position into its elevated position upon its engagement with a respective full bobbin as each unit moves along said ascending side.

4. The device defined in claim 3 wherein each of said doffing forks has a bifurcation provided with spring-loaded catches engageable with the full bobbins on said spindles.

5. The device defined in claim 2 wherein each of said units includes a plate pivotable about an axis perpendicular to said planes and carrying the respective forks, and a pair of ratched-operated catches for retaining said plate in alternate angular positions for ascent of each unit along the ascending side of the triangle and for descent of each unit along said descending side.

6. The device defined in claim 2, further comprising electromagnet means along the triangle for oeprating said locking means.

7. The device defined in claim 6 wherein said spindles are associated with a member displaceable along said path, said device further comprising switch means along said path triggered by said member for energizing said electromagnet means.

8. The device defined in claim 2, further comprising spring means on each of said units for urging said donning fork from its elevated position into its recumbent position.

9. The device defined in claim 8, further comprising a guide bar along the descending side of said chain for elevating said donning fork from its recumbent position into its elevated position on each unit as it passes said bar.

10. The device defined in claim 2 wherein the means for removing full bobbins from said doffing forks including a stripper plate along said descending side engageable with the full bobbins carried by said doffing forks as said doffing forks descend below said stripper plate.

11. The device defined in claim 10 wherein said donning fork is provided with a bifurcation having springloaded catches yieldably engaging said spools.

12. The device defined in claim 2 wherein said magazine means includes a chute opening above the ascending side of said chain, and means including a movable plate for controlledly supplying said spools to said shoes.

13. The device defined in claim 2, further comprising deflecting means engageable with the yarn leading to each full bobbin and blade means positioned to sever the yarn engaged by said deflector means.

14. The device defined in claim 13, further comprising a band extending along said path and engageable with the severed yarn ends for retaining them until winding upon a new spool is initialed.

References Cited UNITED STATES PATENTS 745,466 9/1903 Tichon et a1. 5753 1,122,417 12/1914 Peterson 5753 1,823,374 9/1931 Porter 5752 FOREIGN PATENTS 859,631 1/1961 Great Britain.

DONALD E. WATKINS, Primary Examiner 

